Comparison of airway size with some phenotypic parameters in Dalmatian puppies: a practical method to estimate endotracheal tube size.

Objective: To determine the relationship between 16 phenotypic parameters and the diameter of the tracheal lumen and endotracheal tube size (ETS) in Dalmatian puppies.

Study Design: A prospective nonblinded study.

Animals: Twenty-nine Dalmatian puppies, <5 months of age, referred to the Veterinary Faculty Clinics, Burdur, Turkey.

Materials And Methods: The diameter of the tracheal lumen was assessed using lateral cervical radiographs and the ETS was determined for each puppy. The relationships between ETS and body mass, age, dimensions of carpal and digital pads of the thoracic limb, length of the philtrum and the distance between the philtrum and lateral nasal edges were analysed statistically.

Results: The linear relationships between the ETS and the vertical length of the fourth digital pad (r2 = 0.915), and body mass (r2 = 0.908) were higher than with other parameters. Two predictive formulae for ETS derived from regression lines are: ETS +/- SE (0.20) = [body mass (kg) x 6/10]+2.5 and ETS +/- SE (0.19) = [vertical length of fourth digital pad (cm) x 6] - 2.

Conclusions And Clinical Relevance: These formulae provide a practical guide to ETS selection in Dalmatian puppies.